Abstract

The oil palm (Elaeis guineensis) is a very important source of vegetable oil worldwide. While oil palm cultivation is not currently economically significant in Brazil, there is immense growth potential for this crop in the Amazon region, with no need for deforestation. Fatal yellowing (FY) is a major phytosanitary barrier to the development of oil palm cultivation in the region. Many plantations have been devastated by FY, but its causes are unknown. The objective of this study was to analyze the spatial autocorrelation of FY in the oil palm crop by applying Moran’s Index (I). The experiment was carried out on a large farm (>8000 ha) in the municipality of Acará, in the state of Pará (Brazil), with 139 plots of oil palm of different genetic materials and ages. The number of diseased plants per plot has been recorded since 2001 and used in the analysis. A positive autocorrelation of disease incidence was calculated based on the observations of the current study. By calculation of the Local Moran’s I it was possible to identify the presence of high-incidence regions in the northeast and the central-west areas of the farm and low-incidence areas in the south and the north and in outlying plots. The approach described in this study was useful in identifying regions with the highest occurrence of FY, and could be useful in the management of this disease.

摘要

油棕（Elaeis guineensis）是世界范围内非常重要的植物油来源。虽然目前巴西的油棕种植在经济上并不重要，但这种作物在亚马逊地区具有巨大的增长潜力，无需砍伐森林。致命黄变（FY）是该地区发展油棕种植的主要植物检疫障碍。许多种植园已被 FY 摧毁，但其原因尚不清楚。本研究的目的是应用 Moran 指数 ( I）。该实验是在巴西帕拉州阿卡拉市的一个大型农场（>8000 公顷）上进行的，该农场拥有 139 个不同遗传材料和年龄的油棕地块。自 2001 年以来，每块地块的病株数量已被记录并用于分析。根据当前研究的观察结果计算出疾病发病率的正自相关。通过计算Local Moran's I，可以确定农场东北部和中西部地区的高发区以及南部和北部以及边远地块的低发区。本研究中描述的方法可用于确定 FY 发生率最高的区域，并可用于该疾病的管理。